How can i re-install i-tunes

Question

my i-tunes wont open. in a finder window when i type in i-tunes it cant find anything in computer, folders etc it just seems to of disappeared :/ when i look in applications and try to click on i-tunes it does nothing, and whilst on my travels i did find there there isn't an i-tunes plugin (not sure what that is though to be honest) i keep trying to find a link to download and install i-tunes again, but when i do i get either 2 things, the first was that i downloaded a version which wasn't compatible before my system is too old, then when i did try to download the application that my system has the requirements for, i tried to install it and it refused saying i had a more updated version that that already installed, well if that's the case, where on earth is it? help!! :/

Answer 1

First thought, iTunes should not just disappear like that.  Unless you mistakenly dragged it to the trash or renamed it, it should be there.  If it did mysteriously disappear then it is possible you have serious directory corruption which means that a missing iTunes is the least of your problems right now.
Start with Disk Utility. First, if at all possible make a backup of the drive in its present configuration.  If something goes wrong during repair attempts and makes things worse you will have a backup.  You will have to decide how to work this in the light of any present backups you may have, for example, a backup that may be a few days out of date.  In that case you may want to keep that one and make a second backup of this as they are now, though I realize people often don't have a lot of empty drives sitting around.
Boot from the System Installer disc that came with your computer or is the one for the version you currently have on there, select language if applicable, choose utilities, run Disk Utility and verify (and repair if necessary) the drive. You can verify a drive from DU on your main drive while booted but I have found this can result in incorrect reporting of errors. To repair your drive you have to run it from a drive other than the boot drive anyway.
Next, boot from your drive in Safe Mode (http://docs.info.apple.com/article.html?artnum=107393) and repair permissions.  You can repair permissions while booted from the installer disc but this uses the permissions configuration on the installer disc which may be out of date if you have run any updates on your computer.  Booting your computer to Safe Mode restricts the number of things running on your computer while permissions are being run and does a bit of spring cleaning at the same time.
=Reading=
Resolve startup issues and perform disk maintenance with Disk Utility and fsck - http://docs.info.apple.com/article.html?artnum=106214
Using Disk Utility in Mac OS X 10.4.3 or later - http://docs.info.apple.com/article.html?artnum=302672
Disk Utility's Repair Disk Permissions 10.0-10.6 - http://docs.info.apple.com/article.html?artnum=25751
"Try Disk Utility" (modified from http://support.apple.com/kb/TS1417)
1. Insert the Mac OS X Install disc that came with your computer (Edit: Do not use this disc if it is not the same general version as what you have currently on your computer, e.g. use a Tiger disc for a Tiger drive, not a Panther disc), then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu. (In Mac OS X 10.4 or later, you must select your language first.)
Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.
3. Click the First Aid tab.
4. Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.
5. Select your Mac OS X volume.
6. Click Repair. Disk Utility checks and repairs the disk."
Then boot in Safe Mode, (holding Shift key down at bootup; takes longer to boot this way so be patient), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, reboot when it completes.
Mac OS X: Starting up in Safe Mode - http://docs.info.apple.com/article.html?artnum=107393
What is Safe Boot, Safe Mode? (Mac OS X) - http://support.apple.com/kb/HT1564
Safe Boot takes longer than normal startup - http://docs.info.apple.com/article.html?artnum=107394
Mac OS X 10.4, 10.5- Computer shuts down during Safe Boot - http://support.apple.com/kb/TA24054
As for iTunes, Apple has limited versions available for download.  For Tiger the most recent version is 9.2.1
iTunes 9.2.1 (the newest that will run under Tiger) - http://support.apple.com/kb/dl1056
The installing issue may be because of a receipt left on the computer that tells the installer what has been installed.  Got to the top level of your drive, then Library > Receipts.  There may be several in there dealing with iTunes. Drag them someplace safe (for the moment), then try installing iTunes.  Use Disk Utility to repair permissions again (a good idea to do this before and after installing any major software).  Try iTunes. If iTunes starts up and works okay for a while you can delete those old receipts.